AFP - Ivory Coast leader Alassane Ouattara's forces, backed by French and UN troops, captured his besieged rival Laurent Gbagbo in Abidjan on Monday at the climax of a deadly months-long crisis.

Gbagbo, who has held power since 2000 and stubbornly refused to admit defeat in November's presidential election, was detained and taken to his rival's temporary headquarters, with his wife Simone and son Michel.

A portrait of Ivory Coast's fallen leader Laurent Gbagbo

"The nightmare is over," Ouattara's prime minister, former rebel leader Guillaume Soro, said on the Ouattara camp's television channel.

Ouattara spokeswoman Anne Ouloto told AFP the former first couple had been brought to the Golf Hotel, where Ouattara's camp was for months besieged by Gbagbo's forces, at around 1.00 pm (1300 GMT), shortly after the arrest.

"He's here with his wife and his son Michel. I can see them now," she said, speaking by telephone from the former lagoon-side resort now turned into an armed camp protected by former rebel troops and UN peacekeepers.

The situation in other districts of Abidjan, some still controlled by Gbagbo loyalists, including the downtown business district of Plateau and nearby Cocody, was not immediately clear after Gbagbo's arrest.

Earlier, witnesses had reported seeing pro-Ouattara forces entering Gbagbo's besieged residential compound, from which they had been repeatedly repulsed, while French and UN armoured vehicles deployed on a road nearvy.

Troops from the cocoa-rich nation's former colonial ruler France and from a UN peacekeeping force have been pounding Gbagbo's forces since Sunday in a bid to destroy the heavy weapons they were reportedly using against civilians.

Bodies litter the streets of the wealthy west African nation's commercial capital from days of street-to-street fighting, after Ouattara's forces swept down from the north of the country in a lightning attack last week.

A witness said earlier that French helicopters "fired several missiles into the zone. A large plume of black smoke is rising from around the residence."

"Heavy machine-guns targeted one of the helicopters but it was not hit," the witness added.

A spokesman for the UN mission in Ivory Coast (UNOCI) said its peacekeepers and allies from France's "Licorne" force had aimed to destroy heavy weapons that were being used against civilians.

French President Nicolas Sarkozy's office said the French leader had a phone conversation with Ouattara, a former deputy head of the International Monetary Fund, shortly after Gbagbo was arrested.

UN chief Ban Ki-moon confirmed he had ordered Sunday's attack and repeated UN accusations that the Gbagbo camp had used an offer of talks he made last week "to regroup their forces and redeploy heavy weapons".

France on Monday said its military had taken part in the weekend raids at the UN chief's request, and denied reports that its special forces had take Gbagbo and handed him over to Ouattara's men.

Ouattara said late Sunday he had asked the UN to "neutralise the heavy weapons," and has promised that Gbagbo will face justice for alleged crimes committed during the crisis.

The International Criminal Court's prosecutor has launched a preliminary investigation into the violence in Ivory Coast to see if crimes committed are serious enough to come under its jurisdiction.

The court tries allegations of war crimes, crimes against humanity and genocide.

Both sides have been accused of massacres during the stand-off and ensuing conflict, with mass graves reportedly found near Abidjan and hundreds killed or raped in the western town of Duekoue.

Human Rights Watch has said forces loyal to Ouattara also burned down village, citing new evidence of summary killings of Gbagbo supporters in the far west.

French nationals returning to Paris late Sunday from Abidjan spoke of "chaos" in Ivory Coast's biggest city.

Salif Kone, 40, who had been away for two weeks helping his family in Cocody, told AFP: "It's hell, the apocalypse. In the streets you see charred bodies, burnt cars."

The conflict has also hit supplies of food and water and power, with UN agencies warning of the threat of mass outbreaks of disease including a resurgence of cholera in Abidjan.